Thermal cut-out for electric circuits.



PATENTED MAR. 12, 1907. G. E. PAINTER. THERMAL GUT-OUT FOR ELECTRIC CIRCUITS.

APPLICATION FILED NOV.13, 1906.

2 SHEETSSHEET l.

YPATENTED MAR. 12, 1907-.

, G. E. PAINTER. THERMAL GUT-OUT PQR ELECTRIC CIRCUITS.

APPLICATION FILED NOV-13.1906.

2 SHEETS-SHEBT Gwynne Pa inez --To all whom it may concern:

burned-out UNITED, -SIAT E PATENT OFFICE.

GWYNNEE-L A NTER," OF BALTIMORE) MARYLAND.

THsRMALfour-ouf Eon ELECTRIC} Specification of Letters Patent.

CIRCUITS.

Patented March. 12, 1907.

i Application filed November 13,1966. Serial No. 343.184.

Be it known that I, .GWYNNE E. PAINTER,

a citizen of -the United States, residing. at

- .wire,"'as is often done by-person's desirin to avo1d the necessity of replacing burned-out fuses. .1 I

Notwithstanding.- rigild: inspection laws many fires result from 'ses of too-great carry ng capacity which have either designedly or through-i prance. beenlused to'replace a so, and inmany' instances it has heen found that fuses have'been bridged by wire in such a marmer as'to avoid detection except by an electrical tst of the circuit.

In order to more'efi'ectually limit the carrymgcapacit .of acigcuit, and thus afford better protec ion against fire, I provide the circuit with a non 'epl'aceable fuse, which is preferably concealed from view and so sealed to-prev'ent its removal from the circuit ,without detection. This non-replace: able fuse must not -have a carrying capacity greater than the des' ned capaci ty' of the circuit in which it is toe placed, and it is used in conjunction "with a removable fuse of less carrymg'capacity, so. that in case of a temreplaceable fuse. "is designed to be used with any of the wellporary overload the replaceable fuse will open" the circuit withoiit injunyto" the neu- My 'l lqfirreplaceable fuseknown forms of fuse noyfie nthe marketari'd is erfectly inclo sied in orms the support 'forfllb 'ordinary fuse." I the accompanying drawingsg'l have illus rated two embodiments .of tion; but it is to. be understood forms of devices embodying the Inyi mventhat other ,main features of my invention may bedevised to suit.-

particular requirements and that my inventron is not limited to any particular form of fuse or to details of construction.

Referring to the drawings, Fi ure 1 is a.

plan view of a double-pole fuselock pro: vided with a non-replaceable fuse casing or block w' hichand is in accord-- anoe with my invention. Fig. -2 is a vertical section thereof on line 2 2-of Fig. 1. Fig. 3 is a perspective view of the block with-the base portion separated therefrom. Fig. 4 is 'a horizontal section taken on line 4; 4 of Fig. 2, showing theback of the main section of the block with the non-replaceable fuses.

mounted thereon. Fig. 5 is a detail view. of one of the sprin -clips which holds the can. tridge-fu'se, and the terminal plate to whichit is connected. Fig, 6 is a central vertical/section of a socket designed for reccivin a plu fuse,'said socket havin a non-m5 fuse secured therein; and F ig. 7 is a-horizontal section-taken on line 7-7 of Fig. 6.

The fuse-block illustrated in Figs. '1 to 4, lnclu'sive, is preferably constructed of porcelain or someother f'ragile insulating mater a2 and is made in two partsgorsections A nd B, .Which are cemented or otherwise. secured together. The part or section A constitutes the block proper; upon which the removable fuses C C and the terminals D D are mounted, and said section is made to fit into the base or -receiving section B, the latter serving (if the block-section A. The block shown is of the double-pole type, adapted to removably support the two fuses C G, which may be any of the well-known cartridge-fuses. Said fuses C C are sup orted by mea'nsof spring-clips c and mounted in the usual manner on the block-section A. The clips 0 c are each connected to a conducting-plate d by means of the'screw or bolt e,which secures the clip to the; block, said bolt passing through the base of 'the clip and through said late (I to the back of the block '-.s'ection, W ere it is lock (1 by cess 1n the back of the block-section, as

clearly shown in The co'nduc 'gplate (Zforms the terminal D of the block for secur' the-c cuit-Wire other .terE inaI-QD i1 washer (1, tion by means of a screw d and nut d.- nec'tion -is made from the to the spring-clip c by means of a consists of. a plate d" and which is secured to the, block- 6sec;-

as a cover for the non-replaceable .f uses F F,',which are mounted on the back 0 c 0 ma e in the usual form V a nut e, said nut'occupying a roloo provided want; screw d and washer d thereto. The

terminal plate (1 which. in this instance consists of a piece of fusible wireilra 'ng one end soldered or'othere Wise connected to the n'utd, and thc;other end connected in-a,similar-m anner to the nut c, which with the screw or .bolt hold. the

Said socket comprises a porcelain;casing G,

v made in two sections 9 and g. 'The basei2 and the nuts (Panda; and as thus far dei ,section'g is Inade in the form of a'cup, having J s'c 1 i bed;it 'seen'thatwhen'. the block atwo openings-or'slots g and-gat opposite- 5 is properly'connected in an electriccircuit sides thereof for portions of the terminal 0 current will pass from the terminal D by plates-72, and'h, whichproject through said-- fringclip c, f; Theihack blgclo-seotion is properly recessedjo -receive"the"fuses "F designed capacit'y'of the circuit m hieh it V I rendered'non replaceableby the block- '3 :in hich' the block section A isinserted: The

' "*one' orthe otherlof said sections. WVhen'the' way ofthe screw d, to the fuse F and thence to the cartridge-fuse by way .ofthelnute,

screw e ,'and spring-clip c".through said 10 cartridge-fuse to the'c'lip. c, and thence to. the

line-wire of the circuit throughthe terminal plated. The 'fuseF; which I term the non replaceable: fusey-should be of such size. and

' ual to the 1 l engthfas will carry'aeurrent' e' is tobe placed and which will'fusewh'en' the current is increased beyond said" designed i carrying capacity. The' removable use C 'should have a carrying capacity Iessthan that- 'oft'hefuse F, so that in case'of atemporary overload the 'cartridgefusetwill.burn outbo- "fore any damage can be done to the fuse F. l If'th'e removable"or" oartridge 'fi1se- C be replaced "by another of greater-carrying c'aae it% or said fuse be bridgedfby' a wire','t he se' 1' will operat'efto protect the circuit should the" current be increased beyond the safety-limit'of the,carryingwires. The fuse section B, made in the 'form of; a receptacle,

'two sections A; and Bare, secured together by "rnea'nsof %suitable cement, s0 asto'render 5 them practically ins'e arable, and being made o fragilemateria any attempt to sep-" arate themisli'able .to result breakage of use F burns out, the entire device must be replaced b another. Should either or both of the bloc -sections be broken', .this would be i 'evidence'of an attempt to repair or replace the concealed fuse, in which case the inspecp tor should require a new block to be inserted inthecircu'it'; J

'l have provided the block-section A with projections or flanges a,- whieh'serveto' separate the terminals DandD from each other and from the removablefuses C'() These flanges are forthe purpose of preventing 56 thefuses from'bein'g bridged'acr'os'stheface 'of the block without showing the fact-.- Any wire which'might be used to out out 'the'fuses would have to pass overor around the flanges exposing the connectionnb' thatit' can be readily detected-by the inspector. The fuseblock' should bemarkedin amanner to indicate the carrying capacity of the non-replace I able-fuse,- andthis may be conveniently done l do by stamping-the capacity on sealing-wax which-may be-placed over the joint between the two sections of the block, as shown at a :i Fig! r. f Fi s'. '6- 'and' TI haveillustratedasocket adapter? Inassembling the. arts I "plates, insulating atenal, and the'cupK 1c0 a, andthis' could not beeasily (lone without to receive-a plug-fuse. {Not shown.)

slots'and to which the'terminal wires ofthe I out fracture. Within the cup-section g is a.

bolt-Lhaving ahead iatits upper end and a nut i at itslo'wer end, between which the two terminal platesh and" h are securely '80. clamped, the bolt and plates being properly of insulated from each other; by means of mica or other insulating'material'J. Within the upper section g'rof the casing is a screw-- threaded cup K, adapted to receive the 'screw threaded. end of any .of the .well-kno wn'plugfuses. (No tshewn;)-" ThiscupKhasitsbot-; tom clamped b'y'the bolt'l betweenth'e plate -h' and the insulathig'material'J, so thatsaid' 7' cup is'in electrical contact withthe platehflfge but is insulated from the other metal parts of the device;.x.-- 'Betweenthe bottom of the easing-section g. and the insulatingmaterialJ is 'a piece of fusible wire,'F", having}one- .end'

soldered or otherwise'connected to the nut 5, 5 jandits; other end similarl connected to the' terminal plate-h, said fusib e wire constituting "the non-replaceable fuse/ the are first secured I together in. proper relation by means of the belt I and nut 71', after. which the nut and bolt are soldered or locked together'to prevent separation; and after the 1 non-replaceable fuse issecured whole is placed in the'cup-section o the casing. It is to be noted that the slot '9 in the cup-section of the casing opens-through the edge of-said SOCtiOII tOIIGCGiVQ that portion of theterminal plate h'which projects through I 1.0

,said slot to the outside of thecasing. "After Itheparts' have been properly placed in the 'cup scction of the casing the upper s ectiong is placed on top of the cup-section and cemcnted thereto, said upper section opcratin x 15 to close the sl'ot'g of the-lower section and prevent therc'moval of the metallic parts without fracturing the casing.

The terminal latcs h h are each 'rovided with a screw or connectingthe evicc to me the terminalavires' o'f alcircuit, and when properly connected currcnt will pass from the terminal plate h to the, F and thence through the nuti"and bolt 1- to the plug-fuse, (not'sho\\-'n',') thence through the 125 metallic 'cup K tolthe terminal plate h. In this form-of device the fuses operate to protect the circuit in the manner heretofore described. -v

Otherembodiments of my invention will [3o place the :1 cuit comprising a ,5 ably supporting the fuse of lesser carrying readily suggest themselves to those skilledin the art, the two devices illustrated being" deemed suflicient for the purposes of this.

specification. I believe I am the first t6 pro- 5 tect a-circuit by means of two fuses having different carrying capacities, the fuse limit In invention to the particular arrange' ment 0 the fuses or to the manner inii they may be connectedin the'circuit.

Having thus described my invention, wha

I claim as'new,and desire to secure by Letters Patent, is-" 1. Means capacities connected in series, and a "seblock in which the fuse of greater carrying capacity is sealed against removal without detection.

2. A device for-protecting an electric cirmeans carriedby said fuse-b k for removcapacity, and means for sealing the fuse of greater carryi'n capacity to prevent its removal from sai block Without detection.

o 3. A fuse block of fragile insulating mate- 3 rial provided with suitable binding-posts for connecting it in an electric circuit, a fuse care ried by said 'block, I said f use being s 3 necte' greater carrying capacity being so sealed as to prevent its removal from the circuit with-' out showing the fact, and I do not intend-to for protecting an electric circuit comprising two fuses of different carr 'ng se block two series-6on5 nected'fuses of different carrying capacities,

' against removal therefrom without I fracturing said block.

removably supporting an electric fuse and havin' a fusesealedin said holder and conmeans. 1

comprisin posed oi cess, means a fuse, a casing therefor com said means and said sealed fuse, for the pin,-

6. A device for cuit comprising a se, a two-part casing inclosing said fuse, said casin being sealed against access, and means supporting a second fuse, said means being sealed casing of fragile insulating materia {a fuse inclosed ,therein, and means securedkto the outside of said casing for removably supporting a fuse said means being connect series with thefir'st-mentioned fuse, In testimony whereof I have hereun my hand in presence of two subscribi a ile material sealed against ac-f i or removably supporting a sec: .ond fuse, and suitable connections between rotecting an electric cit connected in series with said inclosed fuse. pi. i 1 7. 'An electric fuse-support comprisln a-iy 4. A fus'e-holderprovided with means for I in series with said iuse-supporting 40 51A device for protecting electric circuits.

.5 r removably 

